Rowing surf board

ABSTRACT

A rowing surf board includes a board having two through holes defined through the board and tow oars are respectively pivotably engaged with the through holes. Each oar has a blade portion which is pivotably connected to a distal end beneath the board such that the blade portion is pivoted to reduce a contact area against water when the blade portion is moved forward.

FIELD OF THE INVENTION

The present invention relates to rowing surf board which includes twooars pivotably connected thereto and each blade of the oar is pivotablerelative to the shank of the oar so as to reduce the resistance whenrowing forward.

BACKGROUND OF THE INVENTION

There are many activities such as surfing, kayaking and/or canoeingrequires a certain level of skill, wherein the surf board has lessamount of volume but it requires skill to keep balance on the wave, thecanoe occupies a larger space which is inconvenience for being carriedor transported. Operation of a canoe requires rowing two oars and eachoar has a blade which is a wider and flat portion such that water can bepushed backward to make the canoe move forward. Nevertheless, when theoars are rowed forward, the wide blade portion generates a resistancewhich makes the user feel tired within a short period of time. A goodcanoeist rotates the blade portions during the oars being moved forwardto reduce the area against the water. This is not an easy job forordinary canoeists.

The present invention intends to provide a rowing surf board which hastwo oars pivotably connected to the surf board and the blade portion ofeach oar is pivotable when the oars are moved forward so that theplayers are suffered less resistance.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, there isprovided a rowing surf board which comprises a board having two throughholes defined through two sides of the board. An oar extends througheach of the through holes and is pivotably engaged with the board at thethrough hole. Each oar has a blade portion pivotably connected theretosuch that the blade portion is pivoted to reduce a contact area againstwater when the blade portion is moved forward.

The present invention will become more obvious from the followingdescription when taken in connection with the accompanying drawingswhich show, for purposes of illustration only, a preferred embodiment inaccordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view to show the rowing surf board of thepresent invention;

FIG. 2 is an exploded view to show the rowing surf board of the presentinvention;

FIG. 3 shows the oar is received in the first slot and the second slot;

FIG. 4 shows that each connection portion has a tapered passage so thatthe oar can be tilted an angle;

FIG. 5 is a top view to show that the oar is received in the first slotand the second slot;

FIG. 6 shows that the blade portion is operated to pull water backward,and

FIG. 7 shows that the blade portion is pivoted an angel when the oar ismoved forward.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, the rowing surf board of the presentinvention comprises a board 10 which is made of foam material andcovered by plastic. The board 10 has two through holes 11 definedthrough the board 10 and located at two sides of the board 10. Two firstslots 12 are defined in a top of the board 10 and communicate with thetwo through holes 11 respectively. Two second slots 13 are defined in anunderside of the board 10 and communicate with the two through holes 11respectively. The first slot 12 and the second slot 13 are located inopposite with each other and share a common axis

An oar 20 extend through each of the through holes 11 and pivotablyengaged with the board 10 at the through hole 11. Each of the oars 20includes a connection portion 21, a first section 22 and a secondsection 23. The connection portion 21 includes a tapered passage 211defined transversely therethrough and a pin 15 extends through a hole ineach side of the board 10, the passage 211 and is threadedly engagedwith a threaded hole 111 in the board 10. An end piece 16 is used toseal an open end of each of the pins 15. The first section 22 isconnected to the connection portion 21 and located above the board 10.An end piece 24 is connected to a distal end of the first section 22.The second section 23 is connected to the connection portion 21 andlocated below the board 10. The blade portion 25 is pivotably connectedto the second section 23. The tapered passage 211 allows the oar 20 totilt an angle during operation as shown in FIG. 4.

Each oar 20 has a blade portion 25 which is pivotably connected thereto.Each of the blade portions 25 has two lugs 251 extending from a sidethereof and the second section 23 is pivotably connected to the two lugs251. Each of the blade portions 25 has a recessed portion 252 definedbetween the two lugs 251 and the second section 23 is removably engagedwith the recessed portion 252.

As shown in FIG. 6, when the oars 20 are rowed backward, the bladeportions 25 are pushed by the water by their maximum area. As shown inFIG. 7, when the oars 20 are rowed frontward, the blade portions 25 arepivoted an angle by the water so that a less contact area is used toagainst the water and this reduces the water resistance.

As shown in FIGS. 3 and 5, the first section 22 and the second section23 can be received in the first slot 12 and the second slot 13respectively when not in use. A plurality of bosses 121 extend from aninside of each of the first slots 12 so as to easily position the firstsections 22 of the oars 20.

The board 10 can be used as a surf board when the oars 20 are positionedin the slots 12, 13, and can be used as a kayak by rowing the two oars20.

While we have shown and described the embodiment in accordance with thepresent invention, it should be clear to those skilled in the art thatfurther embodiments may be made without departing from the scope of thepresent invention.

1. A rowing surf board comprising: a board having two through holesdefined through the board and located at two sides of the board, an oarextending through each of the through holes and pivotably engaged withthe board at the through hole, each oar having a blade portion which ispivotably connected thereto such that the blade portion is pivoted toreduce a contact area against water when the blade portion is movedforward; the board having at least a pair of slots formed in anunderside thereof, each blade portion being retractable to a fullyrecessed position within one of the slots.
 2. The rowing surf board asclaimed in claim 1, wherein two first slots are defined in a top of theboard and communicate with the two through holes respectively, the slotsdefined in the underside of the board being second slots communicatingwith the two through holes respectively, each first slot sharing acommon axis with one of the second slots so that each of the oars isreceived concurrently therein.
 3. The rowing surf board as claimed inclaim 1, wherein a plurality of bosses extend from an inside of each ofthe first slots.
 4. The rowing surf board as claimed in claim 1, whereineach of the oars includes a connection portion, a first section and asecond section, the connection portion including a passage definedtransversely therethrough and a pin extending through the passage andfixedly connected to the board, the first section connected to theconnection portion and located above the board, the second sectionconnected to the connection portion and located below the board, theblade portion pivotably connected to the second section.
 5. The rowingsurf board as claimed in claim 4, wherein each of the blade portions hastwo lugs extending from a side thereof and the second section ispivotably connected to the two lugs.
 6. The rowing surf board as claimedin claim 5, wherein each of the blade portions has a recessed portiondefined between the two lugs and the second section is removably engagedwith the recessed portion.
 7. A rowing surf board comprising: a boardhaving two through holes defined through the board and located at twosides of the board, an oar extending through each of the through holesand pivotably engaged with the board at the through hole, each oarhaving a blade portion which is pivotably connected thereto such thatthe blade portion is pivoted to reduce a contact area against water whenthe blade portion is moved forward; wherein each passage in theconnection portions is a tapered passage so that the oars are tilted atan angle during operation.